all: fix typos

Change-Id: I8f9f58babea80bbdad52df2b67a083f3a381c217
GitHub-Last-Rev: 79ce945721
GitHub-Pull-Request: golang/image#8
Reviewed-on: https://go-review.googlesource.com/c/image/+/389054
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Trust: Tobias Klauser <tobias.klauser@gmail.com>

font/sfnt/gpos.go

@@ -437,7 +437,7 @@ func makeCachedCoverageRange(buf []byte) indexLookupFunc {
 		//	 pairs: 130=0, 131=1, 132=2, 133=3, 134=4, 135=5, 137=6
 		//   ranges: 130, 135, 0    137, 137, 6
 		// startCoverageIndex is used to calculate the index without counting
-		// the length of the preceeding ranges
+		// the length of the preceding ranges
 
 		idx := sort.Search(num, func(i int) bool {
 			return gi <= GlyphIndex(u16(ranges[i*6:]))

font/sfnt/sfnt_test.go

@@ -567,7 +567,7 @@ func TestPostScriptSegments(t *testing.T) {
 	// drawn in a consistent direction. Clockwise for external paths,
 	// anti-clockwise for internal paths. (Actually PostScript requires the
 	// exact opposite, but FontForge reverses PostScript contours when it loads
-	// them so that everything is consistant internally -- and reverses them
+	// them so that everything is consistent internally -- and reverses them
 	// again when it saves them, of course)."
 	//
 	// The .notdef glyph isn't explicitly in the SFD file, but for some unknown

tiff/lzw/reader.go

@@ -30,7 +30,7 @@ Aldus "off by one" algorithm.
 
 The Go code doesn't read (invalid) TIFF files written by old versions of
 libtiff, but the LZW algorithm in this package still differs from the one in
-Go's standard package library to accomodate this "off by one" in valid TIFFs.
+Go's standard package library to accommodate this "off by one" in valid TIFFs.
 */
 
 import (